1、Designation: D6343 10D6343 14Standard Test Methods forThin Thermally Conductive Solid Materials for ElectricalInsulation and Dielectric Applications1This standard is issued under the fixed designation D6343; the number immediately following the designation indicates the year oforiginal adoption or,
2、in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope Scope*1.1 This standard is a compilation of test methods for evaluating properties o
3、f thermally conductive electrical insulation sheetmaterials to be used for dielectric applications.1.2 Such materials are thin, compliant sheets, typically produced by mixing thermally conductive particulate fillers with organicor silicone binders. For added physical strength these materials are oft
4、en reinforced with a woven or nonwoven fabric or a dielectricfilm.1.3 These test methods apply to thermally conductive sheet material ranging from about 0.02 to 6-mm thickness.1.4 The values stated in SI units are to be regarded as standard.NOTE 1There is no IEC publication or ISO standard equivalen
5、t to this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to us
6、e. See also 18.1.2 and 19.1.2.2. Referenced Documents2.1 ASTM Standards:2D149 Test Method for Dielectric Breakdown Voltage and Dielectric Strength of Solid Electrical Insulating Materials atCommercial Power FrequenciesD150 Test Methods for AC Loss Characteristics and Permittivity (Dielectric Constan
7、t) of Solid Electrical InsulationD257 Test Methods for DC Resistance or Conductance of Insulating MaterialsD374M Test Methods for Thickness of Solid Electrical Insulation (Metric)D412 Test Methods for Vulcanized Rubber and Thermoplastic ElastomersTensionD624 Test Method for Tear Strength of Conventi
8、onal Vulcanized Rubber and Thermoplastic ElastomersD792 Test Methods for Density and Specific Gravity (Relative Density) of Plastics by DisplacementD883 Terminology Relating to PlasticsD1000 Test Methods for Pressure-Sensitive Adhesive-Coated Tapes Used for Electrical and Electronic ApplicationsD145
9、8 Test Methods for Fully Cured Silicone Rubber-Coated Glass Fabric and Tapes for Electrical InsulationD1711 Terminology Relating to Electrical InsulationD2240 Test Method for Rubber PropertyDurometer HardnessD5470 Test Method for Thermal Transmission Properties of Thermally Conductive Electrical Ins
10、ulation MaterialsD6054 Practice for Conditioning Electrical Insulating Materials for Testing (Withdrawn 2012)33. Terminology3.1 Definitions:1 These test methods are under the jurisdiction ofASTM Committee D09 on Electrical and Electronic Insulating Materials and are the direct responsibility of Subc
11、ommitteeD09.19 on Dielectric Sheet and Roll Products.Current edition approved Nov. 1, 2010Nov. 1, 2014. Published December 2010November 2014. Originally approved in 1998. Last previous edition approved in 20042010as D6343 99D6343 10.(2004). DOI: 10.1520/D6343-10.10.1520/D6343-14.2 For referencedASTM
12、 standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 The last approved version of this historical standard is referenced on www.astm
13、.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prio
14、r editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 1942
15、8-2959. United States13.1.1 For definitions of terms used in these test methods and associated with electrical and electronic insulating materials, useTerminology D1711.3.1.2 For definitions of terms used in these test methods and associated with plastics, use Terminology D883.3.2 Definitions of Ter
16、ms Specific to This Standard:3.2.1 apparent thermal conductivity, nthe time rate of heat flow, under steady conditions, through unit area, per unittemperature gradient in the direction perpendicular to the area, for a nonhomogeneous material.3.2.1.1 See 16.1 for a discussion of the terms thermal con
17、ductivity and apparent thermal conductivity. To avoid confusion, thesetest methods use apparent thermal conductivity for measurements of homogeneous and nonhomogeneous materials.3.1.2 See Terminologies D1711 and D883 for definitions of other terms used in these test methods.4. Significance and Use4.
18、1 These test methods are useful to determine compliance of thermally conductive sheet electrical insulation with specificationrequirements established jointly by a producer and a user.4.2 These test methods have been found useful for quality assessment. Results of the test methods can be useful in a
19、pparatusdesign.5. Specimen Preparation5.1 From a sample of sufficient size, prepare test specimens of the dimensions and of the quantity to meet the requirements foreach test procedure.6. Conditioning6.1 Unless otherwise specified, condition specimens in accordance with Procedure A of Practice D6054
20、. Perform all tests onspecimens that are in equilibrium with the conditions of Procedure A of Practice D6054. Make the tests in a chamber maintainedat 23 6 2C and 50 6 5 % relative humidity.6.2 When required by a test procedure, condition specimens in accordance with Procedure D of Practice D6054, e
21、xcept thateither distilled or deionized water are permitted to be used. In such cases, remove the specimens from the water into air maintainedat 23 6 2C and 50 6 5 % relative humidity, remove surface water with a paper towel, and begin testing within 30 s.7. Precision and Bias7.1 No evaluation of pr
22、ecision or bias has been established for the test methods herein as they relate to these thin thermallyconductive materials. For general guidance only, it is suitable to make reference to Precision and Bias statements in the referencedtest methods as listed in Section 2.8. Thickness8.1 Significance
23、and UseThe accurate determination of thickness is essential for design purposes for both thermal conductionand electrical insulation. Thickness enters into the calculation of thermal, electrical, and tensile properties.8.2 Procedure:8.2.1 Make thickness measurements on specimens in accordance with T
24、est Methods D374M, Method H. This test method usesa micrometer which applies a pressure of 26 6 4 kPa on the specimen, using a 6.25-mm diameter presser foot.8.2.2 Clean the surfaces where the measurements are to be made. Take five randomly spaced measurements to cover the lengthand width of the spec
25、imen. Take measurements at least 6 mm from the edges of the specimen.NOTE 2At the compressive loads of this test method, some materials will undergo compression or compression deflection. It is important for the buyerand seller to agree on other conditions of pressure, anvil and presser foot geometr
26、y, and the dwell time to be used.8.3 ReportReport the thickness in millimetres as the average of the five measurements.9. Adhesion Strength9.1 Significance and UseMaterials covered by this test method are optionally coated with a pressure sensitive adhesive on oneor both sides. In some cases perform
27、ance in a particular application can be affected by the adhesion strength.9.2 ProcedureTest three specimens of 25-mm width in accordance with Test Methods D1000 except, except clean the steelpanel with isopropyl alcohol.9.3 CalculationFrom the three specimens, calculate the average adhesion strength
28、.9.4 ReportReport the average adhesion strength in newtons per metre of width.10. Breaking Strength10.1 Significance and UseIn some cases, breaking strength is a significant limitation on methods of applying tapes. Hence,measurements of the tensile force they are able to withstand are potentially im
29、portant data.D6343 14210.2 Procedure:10.2.1 Prepare three specimens at least 500 mm long and 25 mm 25 mm wide. If the material contains reinforcing fibers, cutthe test specimen such that the machine direction reinforcing fibers are parallel to the long axis of the specimen. In the case ofmaterials n
30、arrower than 25 mm, test the full width as received.10.2.2 Test the breaking strength in accordance with Test Methods D1458.10.3 CalculationFrom the test measurements on the three specimens, calculate the average breaking strength.10.4 ReportReport the average breaking strength in newtons per metre
31、of width.11. Tensile Strength and Elongation11.1 Significance and UseTensile test results with these materials will vary with specimen geometry and conditions of testing.Hence, these tensile measurements are not always reliable indicators of usefulness in a particular application. Tensile properties
32、of glass-fiber-reinforced materials vary with the ratio of the glass-fiber thickness to the total thickness. Measurements of tensileproperties vary with the direction of the glass fibers with respect to the direction in which the specimen is cut.11.2 Procedure:11.2.1 Prepare three specimens in accor
33、dance with Test Methods D412, using Die C.11.2.2 If the material contains reinforcing fibers, cut the test specimen such that any reinforcing fibers are at 45 6 10 to thelong axis of the specimen.11.2.3 In accordance with Test Methods D412, measure the tensile breaking strength and tensile elongatio
34、n at a jaw separationrate of 500 mm/min (20 in./min).11.3 Calculation:11.3.1 Calculate the tensile strength in kilopascals, using the initial thickness and width for each specimen. Calculate theaverage tensile strength from the three test measurements.11.3.2 Similarly, calculate each elongation at b
35、reak as a percentage of the initial jaw separation. Calculate the average from thethree test measurements.11.4 ReportReport the average tensile strength in kilopascals and the average elongation in percent.12. Hardness12.1 Significance and UseThis test method is empirical and intended for control pu
36、rposes only.12.2 Procedure:12.2.1 Prepare a sufficient number of specimens to form a stack approximately 6 mm high.12.2.2 Determine the indentation hardness in accordance with Test Method D2240, with the following exception:12.2.2.1 Read the scale within 2 s after the presser foot is in firm contact
37、 with the specimen.12.3 CalculationFrom the five measurements taken at different locations on the specimen, calculate the average hardness.12.4 ReportReport the average hardness, in accordance with the Shore Hardness system.13. Specific Gravity13.1 Significance and UseSpecific gravity is a potential
38、ly useful tool to help verify proper filler loading and distribution andit is information occasionally required by designers of specific applications of these materials.13.2 ProcedurePrepare two specimens of at least 650 mm650 mm2 in area and test in accordance with Test Methods D792,Method A-1.13.3
39、 ReportReport the average of the two test measurements as the specific gravity.14. Tear Strength14.1 Significance and Use:14.1.1 In certain applications, these materials are stressed during installation in such a way as to introduce tearing stresses onthe material. Tear strength measurements provide
40、 a means of comparing or specifying materials for such applications.14.1.2 The type of reinforcement, testing rate, and specimen size affect the tear resistance. The results obtained by this testmethod are predictive of performance only under certain specific conditions of use.14.2 Procedure:14.2.1
41、Prepare three specimens using Die C of Test Method D624.14.2.2 If the material contains reinforcing fibers, cut the test specimen such that any reinforcing fibers are at 45 6 10 to thelong axis of the specimen (the “A” dimension of Die C).14.2.3 Measure the tear strength in accordance with Test Meth
42、ods D412, using a jaw separation rate of 500 mm/min (20(20 in.in./min).min).D6343 14314.3 CalculationCalculate the tear strength for each specimen by dividing the maximum force by the specimen thickness.Calculate the average from the three test measurements.14.4 ReportReport the average tear strengt
43、h in newtons per millimetre.15. Thermal Impedance15.1 Significance and UseThermal impedance measurements are affected by applied pressure, thickness, any surfaceirregularities, and uniformity of heat flow. Since the results obtained by these test methods represent thermal characteristics of amateria
44、l under a specific set of conditions, it is not appropriate to use these results to predict performance in an application whereconditions differ from those of the test.15.2 Procedure:15.2.1 Prepare specimens for two determinations, as required by either Method A or Method B of Test Method D5470.15.2
45、.2 Measure the thermal impedance in accordance with Test Method D5470, using a pressure of 3.0 6 0.1 MPa and anaverage specimen temperature of 50 6 5C.15.3 CalculationFrom the two determinations, calculate the average thermal impedance.15.4 ReportReport the average thermal impedance in (m2K)/W and t
46、he test method used.16. Apparent Thermal Conductivity16.1 Significance and UseThermal conductivity applies only to homogeneous materials. Thermally conductive electricallyinsulating materials are heterogeneous since they typically include ceramic fillers and elastomeric binders, and are often reinfo
47、rcedwith glass fiber or a layer of dielectric film. Hence the term apparent thermal conductivity is more appropriate. Because of themultilayer nature of these products, the apparent thermal conductivity will vary with material thickness.16.2 Procedure:16.2.1 Prepare specimens in accordance with eith
48、er Method A or Method B of Test Method D5470.16.2.2 In accordance with Test Methods D5470, determine the thermal impedance of layered stacks using 1, 2, and 3 layers ofspecimens at 3 6 0.1-MPa pressure. Use either Test Method A or Test Method B of Test Method D5470.16.3 CalculationCalculate the appa
49、rent thermal conductivity from the slope of a plot of thermal impedance against specimenstack thickness.16.4 ReportReport the apparent thermal conductivity in W/(mK) and the test method used.17. Permittivity and Dissipation Factor17.1 Significance and UseTest Methods D150 discuss the significance of dielectric properties and dissipation factor.17.2 ProcedurePrepare four specimens. Use 75-mm diameter conducting paint opposed electrodes. Test each specimen at 1kHz in accordance with Test Methods D150 in air at a temperature of 23 6 2C.17
